Grinding attachment for straight edge wood tool blades



N. *,l.` `RIVM-4D 2,636,326

Mmm non April 28, 1953 Y Filed sept. 18, 1951.

8g M ttomegs Patented Apr. 28, 1953 GRINDING ATTACHMENT FOR STRAIGHT EDGE WOOD TOOL BLADES Nelson J. Rivard, Milford, Conn.

Application September 18, 1951, Serial No. 247,142

6 Claims.

This invention relates to a grinding attachment for straight edge wood tool blades, and has for an object to provide a simple and effective means for accurately grinding the blades of Wood-working tools, such, for example, as the blades of the rotary cutter of planers, flat blades of hand planes, chisels, and the like.

Another object is to provide a device of this character which may be mounted on the table of a saw or similar device with a simple operation and hold the blade to be ground in position to engage and be moved across the face ofv a grinding wheel mounted in the table in place of the saw.

With the foregoing and other objects in view, I have devised Vthe construction illustrated in the accompanying drawing forming a part of this specification. It is, however, to be understood the invention is not limited to the specie details of construction and arrangement shown but may embody various changes and modifications within the scope of the invention.

In this drawing:

Fig. l is a top plan view of the device showing it mounted on the saw table in position for grinding a blade;

Fig. 2 is a transverse section substantially on line 2-2 of Fig. l;

Fig. 3 is a similar section showing the device used for a different type of blade;

Fig. 4 is an end view on an enlarged scale with parts broken away to more clearly show the construction;

Fig. 5 is a top plan View of the clamp for the device;

Fig. 6 is an end view of this clamp with the clamping screw removed, and

Fig. 7 is a detail section substantially on line 'l-'l of Fig. 1.

In the drawing the device is shown as mounted on a bed or table III of a wood saw, the saw used with the table when used as a saw being located in the opening I I operating on a transverse shaft I2 driven from any suitable means (not shown).

Before using this device the saw is removed and the grinding wheel I3 substituted for it on the shaft so as to be driven by the same means. Then this device is clamped to the table I0 for grinding the blade on this wheel. In Figs. 1, 2 and 4 it is shown as grinding the long edge I4 of a long flat blade I5, such, for example, as one of the blades of a rotary cutter, in a planar. In Fig. 3 it is shown as grinding the edge I6 at one end of an elongated flat blade I'I of the type used in a hand plane, for example. the position lil v Ul

of this blade being shown in dotted lines in Fig. 1.

The device comprises a guide bar I 8 to rest on the top of the table III and be clamped thereto. Although this bar may be of different shapes it is preferably an angle bar comprising a horizontal iiange I9 to rest on top of the table and an upright guide flange 20. Means is provided for clamping this bar to the table, that shown being a very simple and eiective means for this purpose. It comprises a clamp 2|, also preferably a piece of angle iron, pivoted intermediate its length by a screw 22 passing through one of a series of openings 23 in the horizontal flange I9 of the bar. The top or horizontal flange of the member 2l is cut transversely, as shown at 24, and the flange bent downwardly as shown at 25, tolie over the upright vflange 2B. Then a hole 21 is drilled and tapped through these iianges for the clamping screw 28, which is preferably a thumb screw as shown so it can be operated by hand without tools. By screwing up this thumb screw to clamp its free end against the table the opposite end of the member 2| is also clamped against the table, thus providing a very simple and effective means for clamping the bar I8 to the table. By means of a series of holes 23 the clamps may be adjusted to different positions on the bar I8 to clamp the device on tables of different widths. These clamps are easily released by merely unscrewing the thumb screws 28 to permit removal of the device from the table. The two flanges 25 and 26 permit a greater length of thread for the screw without requiring the addition of a Washer or block for this purpose.

The holder 28 for the blade is mounted to slidelongitudinally on the top of the guide bar I8 and the table top. It preferably comprises a plate 29 on the under side of which it is provided with guide means cooperating with the upright flange 20 of the bar I8. A simple and effective guide means comprises an angle bar 36 including a horizontal iiange 3l secured to the under side of the plate 29 by any suitable means such as the rivets 32, and the other flange 33 extending downwardly at one side of the flange 20. At its opposite ends the top iiange 3l is eut longitudinally as shown at 34 and the end of this flange bent downwardly to form a guide lug 35, so that with the flange 33 on'the outer side of the iiange 20 and the lugs 35 on the opposite or inner side of this flange, they vprovide guide means cooperating with the flange 20 to guide the holder 28' for movement longitudinally of thebar I8 while resting on the top edge of the flange 20 of this bar. The cut 34 is preferably tapered, as indicated in Fig. 4, and made somewhat wider than the thickness of the flange 20 to provide a certain amount of clearance between this guide means and the flange 20, and thus permit limited vertical rocking movement of the holder` 28, so that the blade being held by the helder may yield: somewhat with irregularities in' .the grinding wheel.. The amount of this movement may be adjusted by means of adjustable screws 36 mounted in the' upright ange 33 to engage the outer side of the flange 28, and held in adjustedpcsitons by lock nuts 37. It is preferred to use two of these screws 36 located adjacent opposite endsr-cf. the table, as shown in Fig. 1. Y Y

Located forwardly of the gru-ide bar i8 the holder 28 and plate 29 are guided and supported on the top of the table` by a second guiding and supporting means. Although this may be of different shapes it. i's preferably also an angle bar 38 having a horizontal flange 39' secured to the under side ofthe plate 29y by the clamping screws de, and its upright ange 4l either resting on or supported a slight distance'above the top ofthe table i6. Its lower edge may rest directly on this table or felt fiber pads 42. may be mounted on this flange by any suitable means', such as screws d3, with their lower edges engaging the top of thetable, and with these pads saturated with oil they' provide a lubricating'means. asv well as a resilient slightly yielding means -to support the forward' portion of the plate 2Q on. the table.

Means is provided for clamping thev blade on the holder`28' and plate 29' in Vposition for the grinding operation. The clamp shown is a very simple and effective one comprising inverted channel shaped members 44 and l5 of anysuitable lengths. For clamping the long hat blade l' it is preferred to `use threevof these members as shown in Fig.. l with a relatively` long clarn'p All in the center and shorter clamps 4:5 at the opposite ends to thoroughly' clamp vthe blade for its full length, and they are set up or clamped' on the blade by suitable thumb nuts 46 on thescrews1v y 4B.

illus with. the edge of one ilange 4T resting on the blade and the edge of the other flange i8 either resting. on the top ofl the. plate 29 or a shim. or spacer plate under it, not shown, setting up the thumb nuts fils" will effectively tighten and' plate 29 accurately lined up with the guide bar i8 and in the proper position with. its cuttingedgeresting againstY the face of the grinding wheel i3 for accurate and. eflective grinding of this. edge. In. the grinding operation the holder 28 ofthe blade is merely .sl'idback andI forth longi tudinally ofthe bar f8 to carry thefcuttihg edge id of the blade across the f'ace of the. grinding Wheel t3. The' proper positioning, of the blade with respect. to the wheel' may be effected by adjusting the bar I8 on the table Hl and. raising or lowering the table by the usual adjusting means (not shown). employed for. this purpose.. litv is also preferred to provide meansV for lubricating the top edge. of the upright-'flange 2li ofi the bar I8. For thisy purpose the horizontai flange 3|. of.

for example, as that used in hand planes, a chisel or the like, it is merely clamped for example under the clamp 44, as shown in dotted lines Il in Fig. l Vor' full lines Fig. 3. To assist in properly ylining up this blade so as to accurately place it at right angles to the bar i8, the top surface of the plate V29V may be provided with any desired number of gauge lines 52 accurately arranged at right angles to the bar I8, and the edge of the blade il may be properly positioned with respect to these lines to line up the blade, after which it is clamped in thatpositiou.

It Will befundersteod from the above that the device is a very simple one and may be very quickly and accurately mounted on the table, for example', of a sawv` for grinding the blade. The same device canl be used for grinding either the cutting edge of a long narrow blade such, for exam-ple; as those' used in the rotating cutter of a pianer or the like, or the end edge of a narrow blade such, for example, as these used in hand planes and similar'devices. The device may be made at small cost, 'andE does not require any separate power driving means or complicated mechanism as is now employed in grinding devices forV these blades.

Having thus set forth the nature of my invention, claim v 1'. A grindingattaehment of the character described comprising aguide bar to rest on a saw table, spaced clamps mounted en the bar to clamp to opposite edgesof" the table, a holder im` a blade tube' ground resting on the topy of the bar so as to be supported thereby and provided with guide means on opposite sides of the bar and co operatingtherewith to guide the holder for movement longitudinally of the bar, said guide means beingsufciently'spaced from the sides of the bar to permit limited vertical rocking movement of the holder on the bar", a` second guide means on the holder spaced forwardly' of the barito' rest on the table top to Support the forward part of the holder duringl this movement', and clamping means on the holder for securing a blade to be ground in position to move with the holder` across and. in engagement with the face of a grinding wheel' in the table.

2. A grinding attachment oi' the character described including; a guide bar to rest on a saw table comprising an angle bar havingv a horizontal iiange to'rest' on the table and an upright guide liange, means to clamp the bar onthe table, a holder for a blade to' be ground resting on the top edge of the upright flange so as to be supported thereby and including means cooperating with the oppositesides of. this flange to guide the holder for longitudinal sliding' movement, a secondV guide bar on the under side of the holder spaced forwardly of said angle bar to rest on the table top``and a clamp on the holder to clamp the bladeV with its kedge extending forwardly to engage and move across theface of a grinding wheel in the table.

p 3'. A grind'ingattachment of" the character described including a guide bar to rest on a saw the guide 3U' may be drilled as shown in lg. 7 7.5 table QOmPiSg 211 angle bal' having lOrzontal ange to rest on the table and an upright guide flange, means to clamp the bar on the table, a holder for a blade to be ground comprising a plate resting on the top edge of the upright ange so as to be supported thereby, spaced guide means on the under side of the plate cooperating with the opposite sides of said ange to guide the plate for longitudinal movement and having suioient clearance on opposite sides of the flange permitting limited vertical rocking movement of the holder on the ange. a second guide bar mounted on the under side of the plate spaced forwardly of the lrst bar to support the forward portion of the plate on the table, and a clamp on the top of the plate to releasably clamp a cutter blade on top of the plate with its cutting edge extending forwardly from the plate in position to engage and move across the face of a grinding Wheel in the table.

4. A grinding attachment of the character described including a guide bar to rest on a saw table comprising an angle bar having a horizontal flange to rest on the table and an upright guide flange, means to clamp the bar on the table comprising a clamping member pivotally connected intermediate its length to the horizontal flange adjacent each end of the bar to swing about a vertical axis and a screw at one end of said member to engage an edge of the table and clamp the other end of Said member against said edge. a blade holder resting on the upright liange and having guiding means on the opposite sides of and cooperating with said ange to guide the holder for longitudinal movement, and a clamp on the holder to clamp a cutter blade with its cutting edge extending forwardly to engage and move across the face of a grinding wheel in the table.

5. A grinding attachment of the character described comprising a guide bar to rest on a saw table, means to clamp the bar on the table, a holder for a blade to be ground resting on the bar and provided with guide means cooperating with opposite sides of the bar to guide the holder for longitudinal movement and having sufcient clearance to permit limited vertical rocking movement of the holder, a second guide on the under side of the holder spaced forwardly of the guide bar and including a yieldable resilient member to rest on the top of the table and form a yieldable support for the forward portion of the holder. and a clamp on the holder to clamp a cutter blade thereon with its cutting edge extending forwardly in position to engage and move across the face of a grinding wheel in the table.

6. A grinding attachment of the character described including a guide bar to rest on a saw table comprising an angle bar having a horizontal flange to rest on the table and an upright guide ange, clamps on the bar to secure it on the table, means for mounting the clamps at different longitudinal positions on the bar, a blade holder comprising a plate resting on top of said upright flange and provided with guide means on the opposite sides of and cooperating with this flange to guide the plate'for longitudinal movement and having suicient clearance to permit limited vertical rocking movement of the plate, a guide bar on the under side of the plate spaced forwardly of the rst bar to support the plate on the table, and clamping means for a cutter blade on the table, and clamping means for a cutter blade on top of the plate including a stop to engage the rear edge of the blade to position it on the plate and a clamp to engage the top of the blade and clamp it to the plate with its cutting edge extending forwardlyiin position to engage and move across the face of a grinding wheel in the table.

NELSON J. RIVARD.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,040,687 Johnson Oct. 8, 1912 1,206,791 Anderson et al. Dec. 5, 1916 1,275,208 Bockshe Aug. 13, 1918 1,279,025 Shay Sept. 17, 1918 1,694,560 Parish Dec. 11, 1928 1,915,247 Holloway et al. June 20, 1933 2,008,943 Bodey July 23. 1935 2,052,837 Makaroi Sept. 1, 1936 2,458,347 Christiansen Jan. 4. 1949 2,565,291 Amendola Aug. 21, 1951 

